16505693 has 4 divisors (see below), whose sum is σ = 16514940. Its totient is φ = 16496448.

The previous prime is 16505683. The next prime is 16505701. The reversal of 16505693 is 39650561.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 39650561 = 4903 ⋅8087.

It can be written as a sum of positive squares in 2 ways, for example, as 13344409 + 3161284 = 3653^2 + 1778^2 .

It is a cyclic number.

It is not a de Polignac number, because 16505693 - 2⁴ = 16505677 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16505603) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 998 + ... + 5831.

It is an arithmetic number, because the mean of its divisors is an integer number (4128735).

Almost surely, 2^16505693 is an apocalyptic number.

It is an amenable number.

16505693 is a deficient number, since it is larger than the sum of its proper divisors (9247).

16505693 is an equidigital number, since it uses as much as digits as its factorization.

16505693 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9246.

The product of its (nonzero) digits is 24300, while the sum is 35.

The square root of 16505693 is about 4062.7199017407. The cubic root of 16505693 is about 254.6114446371.

The spelling of 16505693 in words is "sixteen million, five hundred five thousand, six hundred ninety-three".